Kadokawa released a new trailer for the KonoSuba: God’s Blessing on This Wonderful World Season 3 “Bonus Stage” OVA, along with visuals for four guest characters. The voice actors and names of the characters will be revealed at a later date.

In Japan, theaters will begin to screen the KonoSuba: God’s Blessing on This Wonderful World Season 3 OVA on March 14. It will run for two week and have two unaired episodes, titled “Red Stream Explosion!” and “Nisemono Chūi!.”
Between March 14 and March 20, fans who watch the OVA will receive a bonus novel written by Natsume Akatsuki titled Winter Shogun Returns. Afterward, the OVA will be available on Blu-ray and DVD on April 25, with an original text story by Akatsuki. The theater screenings will offer the OVA Blu-ray and DVD nearly a month before the retail release.
KonoSuba Season 3 premiered in April 2024 and ran for 11 episodes. Takaomi Kanasaki directed the anime at studio Drive alongside Yujiro Abe. Makoto Uezu and Koichi Kikuta are the scriptwriter and character designer, respectively. Moreover, Masato Kōda is the anime’s composer.
Lastly, here’s a description of the anime, via Crunchyroll:
After a traffic accident, Kazuma Sato’s disappointingly brief life was supposed to be over, but he wakes up to see a beautiful girl before him. She claims to be a goddess, Aqua, and asks if he would like to go to another world and bring only one thing with him. Kazuma decides to bring the goddess herself, and they are transported to a fantasy world filled with adventure, ruled by a demon king. Now Kazuma only wants to live in peace, but Aqua wants to solve many of this world’s problems, and the demon king will only turn a blind eye for so long…